file.access               package:base               R Documentation

_A_s_c_e_r_t_a_i_n _F_i_l_e _A_c_c_e_s_s_i_b_i_l_i_t_y

_D_e_s_c_r_i_p_t_i_o_n:

     Utility function to access information about files on the user's
     file systems.

_U_s_a_g_e:

     file.access(names, mode = 0)

_A_r_g_u_m_e_n_t_s:

   names: character vector containing file names.

    mode: integer specifying access mode required.

_D_e_t_a_i_l_s:

     The 'mode' value can be the exclusive or of the following values

     _0 test for existence.

     _1 test for execute permission.

     _2 test for write permission.

     _4 test for read permission.

     Permission will be computed for real user ID and real group ID
     (rather than the effective IDs).

_V_a_l_u_e:

     An integer vector with values '0' for success and '-1' for
     failure.

_N_o_t_e:

     This is intended as a replacement for the S-PLUS function
     'access', a wrapper for the C function of the same name, which
     explains the return value encoding.  Note that the return value is
     *false* for *success*.

_S_e_e _A_l_s_o:

     'file.info'

_E_x_a_m_p_l_e_s:

     fa <- file.access(dir("."))
     table(fa) # count successes & failures

